import {
    markNodeData,
    objectAssign,
    arrayFindIndex,
    getChildState,
    reInitChecked,
    getPropertyFromData,
    isNull,
    NODE_KEY
} from '../tool/util';
// #ifdef VUE3
import { reactive } from 'vue';//为了兼容vue3
// #endif

const getStore = function (store) {
    let thisStore = store;

    return function () {
        return thisStore;
    }
}

let nodeIdSeed = 0;

export default class Node {
    constructor(options) {
        this.time = new Date().getTime();
        this.id = nodeIdSeed++;
        this.text = null;
        this.checked = false;
        this.indeterminate = false;
        this.data = null;
        this.expanded = false;
        this.parentId = null;
        this.visible = true;
        this.isCurrent = false;

        for (let name in options) {
            if (options.hasOwnProperty(name)) {
                if (name === 'store') {
                    this.store = getStore(options[name]);
                } else {
                    this[name] = options[name];
                }
            }
        }

        if (!this.store()) {
            throw new Error('[Node]store is required!');
        }

        // internal
        this.level = 0;
        this.loaded = false;
        // #ifndef VUE3
        this.childNodesId = [];//vue2版本
        // #endif
        // #ifdef VUE3
        this.childNodesId = reactive([]);//为了兼容vue3
        // #endif
        this.loading = false;
        this.label = getPropertyFromData(this, 'label');
        this.key = this._getKey();
        this.disabled = getPropertyFromData(this, 'disabled');
        this.nextSibling = null;
        this.previousSibling = null;
        this.icon = '';

        this._handleParentAndLevel();
        this._handleProps();
        this._handleExpand();
        this._handleCurrent();

        if (this.store().lazy) {
            this.store()._initDefaultCheckedNode(this);
        }

        this.updateLeafState();
    }

    _getKey() {
        if (!this.data || Array.isArray(this.data)) return null;

        if (typeof this.data === 'object') {
            const nodeKey = this.store().key;
            const key = this.data[nodeKey];

            if (typeof key === 'undefined') {
                throw new Error(`您配置的node-key为"${nodeKey}"，但数据中并未找到对应"${nodeKey}"属性的值，请检查node-key的配置是否合理`)
            }

            return key;
        }

        throw new Error('不合法的data数据');
    }

    _handleParentAndLevel() {
        if (this.parentId !== null) {
            let parent = this.getParent(this.parentId);

            if (this.store().isInjectParentInNode) {
                this.parent = parent;
            }

            // 由于这里做了修改，默认第一个对象不会被注册到nodesMap中，所以找不到parent会报错，所以默认parent的level是0
            if (!parent) {
                parent = {
                    level: 0
                }
            } else {
                const parentChildNodes = parent.getChildNodes(parent.childNodesId);
                const index = parent.childNodesId.indexOf(this.key);
                this.nextSibling = index > -1 ? parentChildNodes[index + 1] : null;
                this.previousSibling = index > 0 ? parentChildNodes[index - 1] : null;
            }
            this.level = parent.level + 1;
        }
    }

    _handleProps() {
        const props = this.store().props;

        if (this.store().showNodeIcon) {
            if (props && typeof props.icon !== 'undefined') {
                this.icon = getPropertyFromData(this, 'icon');
            } else {
                console.warn('请配置props属性中的"icon"字段')
            }
        }

        this.store().registerNode(this);

        if (props && typeof props.isLeaf !== 'undefined') {
            const isLeaf = getPropertyFromData(this, 'isLeaf');
            if (typeof isLeaf === 'boolean') {
                this.isLeafByUser = isLeaf;
            }
        }
    }

    _handleExpand() {
        if (this.store().lazy !== true && this.data) {
            this.setData(this.data);

            if (this.store().defaultExpandAll) {
                this.expanded = true;
            }
        } else if (this.level > 0 && this.store().lazy && this.store().defaultExpandAll) {
            this.expand();
        }

        if (!Array.isArray(this.data)) {
            markNodeData(this, this.data);
        }

        if (!this.data) return;

        const defaultExpandedKeys = this.store().defaultExpandedKeys;
        const key = this.store().key;
        if (key && defaultExpandedKeys && defaultExpandedKeys.indexOf(this.key) !== -1) {
            this.expand(null, this.store().autoExpandparent);
        }
    }

    _handleCurrent() {
        const key = this.store().key;

        if (key && this.store().currentNodeKey !== undefined && this.key === this.store().currentNodeKey) {
            this.store().currentNode = this;
            this.store().currentNode.isCurrent = true;
        }
    }

    destroyStore() {
        getStore(null)
    }

    setData(data) {
        if (!Array.isArray(data)) {
            markNodeData(this, data);
        }

        this.data = data;
        this.childNodesId = [];

        let children;
        if (this.level === 0 && Array.isArray(this.data)) {
            children = this.data;
        } else {
            children = getPropertyFromData(this, 'children') || [];
        }

        for (let i = 0, j = children.length; i < j; i++) {
            this.insertChild({
                data: children[i]
            });
        }
    }

    contains(target, deep = true) {
        const walk = function (parent) {
            const children = parent.getChildNodes(parent.childNodesId) || [];
            let result = false;
            for (let i = 0, j = children.length; i < j; i++) {
                const child = children[i];
                if (child === target || (deep && walk(child))) {
                    result = true;
                    break;
                }
            }
            return result;
        };

        return walk(this);
    }

    remove() {
        if (this.parentId !== null) {
            const parent = this.getParent(this.parentId);
            parent.removeChild(this);
        }
    }

    insertChild(child, index, batch) {
        if (!child) throw new Error('insertChild error: child is required.');

        if (!(child instanceof Node)) {
            if (!batch) {
                const children = this.getChildren(true);
                if (Array.isArray(children) && children.indexOf(child.data) === -1) {
                    if (typeof index === 'undefined' || index < 0) {
                        children.push(child.data);
                    } else {
                        children.splice(index, 0, child.data);
                    }
                }
            }

            objectAssign(child, {
                parentId: isNull(this.key) ? '' : this.key,
                store: this.store()
            });
            child = new Node(child);
        }
        child.level = this.level + 1;

        if (typeof index === 'undefined' || index < 0) {
            this.childNodesId.push(child.key);
        } else {
            this.childNodesId.splice(index, 0, child.key);
        }
        this.updateLeafState();
    }

    insertBefore(child, ref) {
        let index;
        if (ref) {
            index = this.childNodesId.indexOf(ref.id);
        }
        this.insertChild(child, index);
    }

    insertAfter(child, ref) {
        let index;
        if (ref) {
            index = this.childNodesId.indexOf(ref.id);
            if (index !== -1) index += 1;
        }
        this.insertChild(child, index);
    }

    removeChild(child) {
        const children = this.getChildren() || [];
        const dataIndex = children.indexOf(child.data);
        if (dataIndex > -1) {
            children.splice(dataIndex, 1);
        }

        const index = this.childNodesId.indexOf(child.key);

        if (index > -1) {
            this.store() && this.store().deregisterNode(child);
            child.parentId = null;
            this.childNodesId.splice(index, 1);
        }

        this.updateLeafState();
    }

    removeChildByData(data) {
        let targetNode = null;

        for (let i = 0; i < this.childNodesId.length; i++) {
            let node = this.getChildNodes(this.childNodesId);
            if (node[i].data === data) {
                targetNode = node[i];
                break;
            }
        }

        if (targetNode) {
            this.removeChild(targetNode);
        }
    }

    // 为了避免APP端parent嵌套结构导致报错，这里parent需要从nodesMap中获取
    getParent(parentId) {
        try {
            if (!parentId.toString()) return null;
            return this.store().nodesMap[parentId];
        } catch (error) {
            return null;
        }
    }

    // 为了避免APP端childNodes嵌套结构导致报错，这里childNodes需要从nodesMap中获取
    getChildNodes(childNodesId) {
        let childNodes = [];
        if (childNodesId.length === 0) return childNodes;
        childNodesId.forEach((key) => {
            childNodes.push(this.store().nodesMap[key]);
        })
        return childNodes;
    }

    expand(callback, expandparent) {
        const done = () => {
            if (expandparent) {
                let parent = this.getParent(this.parentId);
                while (parent && parent.level > 0) {
                    parent.expanded = true;
                    parent = this.getParent(parent.parentId);
                }
            }
            this.expanded = true;
            if (callback) callback();
        };

        if (this.shouldLoadData()) {
            this.loadData(function (data) {
                if (Array.isArray(data)) {
                    if (this.checked) {
                        this.setChecked(true, true);
                    } else if (!this.store().checkStrictly) {
                        reInitChecked(this);
                    }
                    done();
                }
            });
        } else {
            done();
        }
    }

    doCreateChildren(array, defaultProps = {}) {
        array.forEach((item) => {
            this.insertChild(objectAssign({
                data: item
            }, defaultProps), undefined, true);
        });
    }

    collapse() {
        this.expanded = false;
    }

    shouldLoadData() {
        return this.store().lazy === true && this.store().load && !this.loaded;
    }

    updateLeafState() {
        if (this.store().lazy === true && this.loaded !== true && typeof this.isLeafByUser !== 'undefined') {
            this.isLeaf = this.isLeafByUser;
            this.childNodesId.length > 0 ? this.isLeaf = false : null//TODO:FIXME:我加的修复append 节点时不显示展开图标
            return;
        }
        const childNodesId = this.childNodesId;
        if (!this.store().lazy || (this.store().lazy === true && this.loaded === true)) {
            this.isLeaf = !childNodesId || childNodesId.length === 0;
            return;
        }
        this.isLeaf = false;
    }

    setChecked(value, deep, recursion, passValue) {
        this.indeterminate = value === 'half';
        this.checked = value === true;

        if (this.checked && this.store().expandOnCheckNode) {
            this.expand(null, true)
        }

        if (this.store().checkStrictly) return;
        if (this.store().showRadio) return;

        if (!(this.shouldLoadData() && !this.store().checkDescendants)) {
            let childNodes = this.getChildNodes(this.childNodesId);
            let {
                all,
                allWithoutDisable
            } = getChildState(childNodes);

            if (!this.isLeaf && (!all && allWithoutDisable)) {
                this.checked = false;
                value = false;
            }

            const handleDescendants = () => {
                if (deep) {
                    let childNodes = this.getChildNodes(this.childNodesId)
                    for (let i = 0, j = childNodes.length; i < j; i++) {
                        const child = childNodes[i];
                        passValue = passValue || value !== false;
                        const isCheck = child.disabled ? child.checked : passValue;
                        child.setChecked(isCheck, deep, true, passValue);
                    }
                    const {
                        half,
                        all
                    } = getChildState(childNodes);

                    if (!all) {
                        this.checked = all;
                        this.indeterminate = half;
                    }
                }
            };

            if (this.shouldLoadData()) {
                this.loadData(() => {
                    handleDescendants();
                    reInitChecked(this);
                }, {
                    checked: value !== false
                });
                return;
            } else {
                handleDescendants();
            }
        }

        if (!this.parentId) return;

        let parent = this.getParent(this.parentId);
        if (parent && parent.level === 0) return;

        if (!recursion) {
            reInitChecked(parent);
        }
    }

    setRadioChecked(value) {
        const allNodes = this.store()._getAllNodes().sort((a, b) => b.level - a.level);
        allNodes.forEach(node => node.setChecked(false, false));
        this.checked = value === true;
    }

    getChildren(forceInit = false) {
        if (this.level === 0) return this.data;
        const data = this.data;
        if (!data) return null;

        const props = this.store().props;
        let children = 'children';
        if (props) {
            children = props.children || 'children';
        }

        if (data[children] === undefined) {
            data[children] = null;
        }

        if (forceInit && !data[children]) {
            data[children] = [];
        }

        return data[children];
    }

    updateChildren() {
        let childNodes = this.getChildNodes(this.childNodesId);
        const newData = this.getChildren() || [];
        const oldData = childNodes.map((node) => node.data);

        const newDataMap = {};
        const newNodes = [];

        newData.forEach((item, index) => {
            const key = item[NODE_KEY];
            const isNodeExists = !!key && arrayFindIndex(oldData, data => data[NODE_KEY] === key) >= 0;
            if (isNodeExists) {
                newDataMap[key] = {
                    index,
                    data: item
                };
            } else {
                newNodes.push({
                    index,
                    data: item
                });
            }
        });

        if (!this.store().lazy) {
            oldData.forEach((item) => {
                if (!newDataMap[item[NODE_KEY]]) this.removeChildByData(item);
            });
        }

        newNodes.forEach(({
            index,
            data
        }) => {
            this.insertChild({
                data
            }, index);
        });

        this.updateLeafState();
    }

    loadData(callback, defaultProps = {}) {
        if (this.store().lazy === true &&
            this.store().load && !this.loaded &&
            (!this.loading || Object.keys(defaultProps).length)
        ) {
            this.loading = true;

            const resolve = (children) => {
                this.loaded = true;
                this.loading = false;
                this.childNodesId = reactive([]);
                this.doCreateChildren(children, defaultProps);
                this.updateLeafState();

                callback && callback.call(this, children);
            };

            this.store().load(this, resolve);
        } else {
            callback && callback.call(this);
        }
    }
}
